SVN bad behaviour makes what is written in the book wrong.

[Daniel Shahaf]

C. Michael Pilato wrote on Fri, Mar 29, 2013 at 13:59:44 -0400:
> On 03/29/2013 12:33 PM, Daniel Shahaf wrote:
> > I'm not sure what's the extent of the moving-around of content is.
> > Would "Manually set a custom XML tag on every <section2/> in every old
> > version of the book" be a feasible and semiautomable (i.e.,
> > automable for those <section2/>s that did _not_ move around, and manual
> > for the rest) process? [1]  The build process would then be patched to
> > render those tags as <link rel='canonical'/>.
> 
> The word "manual" is disallowed in this conversation.  :-)  Also, I'd prefer
> that the DocBook sources be, you know, valid DocBook as much as possible. 

I assumed using a new xml namespace would address this problem.

> Further, the problem won't be with <sect2>'s that have moved so much as for
> <sect3>'s -- the <link> tag is scoped to cover the entire page, and we can't
> really say on a <sect3>-by-<sect3> -- or, in the extreme case --
> <para>-by-<para> basis where the updated content might live.  And it makes
> sense that we'd have this limitation, as the <link rel="canonical"> tag was
> designed to help search engines canonicalize their links to the /exact same
> content/ reachable by different URLs.  Our use of it for the purposes of
> trying to point folks intentionally to /different/ content is not in keeping
> with that design.
> 

Okay...

> It might be more sensible to add header/footer matter to all the old book
> version which says, "Hey, please note that you're reading a really old
> version of this content, which is fine if you're still running the matching
> really old version of Subversion.  Otherwise, we strongly suggest that you
> visit http://svnbook.red-bean.com/ and peruse the appropriate version of
> this book."

Yes, a prominent header saying "Hey, unless you are running Subversion
1.1, you *really* want to read [this newer version] instead" would also
solve the problem.